With regard to fixed-, moving- and fluidised-bed reactors treating with non-catalytic gas-solid reactions, seven operational models which consist of the mass-balance equations and boundary conditions under an isothermal condition are established. These models are analytically solved to give both the fractional conversion of solid particles and the exit concentration of the gaseous reactant.When the fractional conversion of solid particles is specified with a given particle diameter, inlet gas concentration and reaction temperature, the reactor performances on the solid particles-output in the continuous reaction operation as compared with batch-wise fixed-bed operation can be estimated by means of the evaluation of a dimensionless ratio such as δτ⁄\varphi(=Sθ⁄(1−ε)Lρp). Calculated results indicate that among the three types of the reactor, the moving-bed reactor has the highest performance capacity. The co-current operation is superior to the counter-current operation within a range of α=0.1∼10, whereas the latter to the former at α<0.1. Both the operations have a nearly equal capacity under the condition of α>10. Also, the reactor performance on the output of particles of the continuous fluidised-bed reactor is inferior to that of the fixed-bed reactor.With increasing fractional conversion of solid particles, the reaction or retention time of the particles is prolonged. In this sense, the continuous fluidised-, counter-current moving-, co-current moving- and fixed-bed reactors become lower in efficiency in its order. In case of the continuous fluidised-bed reactor of the lowest efficiency, the feed rate of solid particles at \barf1=0.98 should be held as small as one-twentieth of the value at \barf1=0.7.
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